1. Welcome to Earth Science

2. Mapping our World
Chapter 2

3. EES News and Notes
If you are not doing so hot, remember to come visit me today or tomorrow during lunch time to learn how to improve your grade.
This is MANDATORY if you are currently below a 70% in class.
We’ll practice a bit more conversion work today
Then, we’ll get a chance to do some group work on our various projects
We’ll end today by taking notes in the new section of material, Chapter 2

4. The Science of Map Making
Cartography: The science of mapmaking.
Cartographers use an imaginary grid of parallel lines and vertical lines to locate exact points on the Earth.

5. Equator
Equator: imaginary line that circles Earth halfway between the north and south poles.
The equator separates Earth into equal halves called north and south hemispheres.

6. Latitude Latitude: lines running parallel to the equator.
Latitude = distance of degrees north or south of the equator.
The equator is a reference point numbered at zero degrees (0°) latitude.
Latitude starts at 0° latitude and runs to 90° latitude at the poles.

8. Degrees of Latitude
Each degree of latitude is equivalent to about 111 km (68.9 miles) on the Earth’s surface
How did cartographers (map makers) decide this?
Earth is a sphere = 360°
Earth’s circumference = 40,000 km
40,000 / 360° = 111 km/degree

9. Latitude
Cartographers can also get more precise by breaking down degrees of latitude into 60 smaller units, called ‘minutes.’
The symbol for minutes: ’
Each minute (’) of latitude is km
To get more precise, you can break down latitude into seconds (”).

10. Bell Ringer – Half Sheet of Paper
How many grams of sand are there in a kg bag of sand?
What is the invisible line called that represents 0° Latitude separating the north and south hemispheres?
What is the main problem with describing coordinates with only degrees and not minutes or seconds?

11. EES News and Notes
If you are not doing so hot, remember to come visit me today during lunch time to learn how to improve your grade.
This is MANDATORY if you are currently below a 70% in class.
We’ll get a chance to do some group work on our various projects
We’ll end today by taking notes in the new section of material, Chapter 2
We’ll practice a bit more conversion work today

12. Longitude
Longitude: Locating positions in east and west directions, also known as meridians.
Prime Meridian: Reference point for longitude.
Equal to 0° longitude
Crosses through Greenwich, England
Points west of the prime meridian are numbered 0° to 180° west (W) longitude
Points east of the prime meridian are numbered 0° to 180° east (E) longitude

14. Stop and Think
What are some of the main differences that you see between the way that latitude is divided versus longitude?
Latitude = Parallel
Longitude = start and stop at same point; orange slices

15. Latitude vs Longitude

16. Semicircles
Unlike lines of latitude, lines of longitude are not parallel. They are large semicircles that extend vertically from pole to pole.
Both latitude and longitude are needed to precisely locate a point on the Earth.

17. Degrees of Latitude vs. Longitude
Degrees of latitude cover roughly the same distances everywhere.
Degrees of longitude vary with location.
A degree of longitude will be as large as 111 km at the equator
A degree of longitude will be closer to 0 km at the north pole or south pole

18. Using Coordinates
For a precise location, we need to use both degrees of latitude and degrees of longitude.
What’s wrong with saying that Charlotte, NC is along the 35°14’N line of north latitude?
What’s wrong with saying that Charlotte is along the 80°15’ W line of longitude?
Charlotte is located at 35°14’N 80°15’ W.

19. Time Zones
Earth is divided into 24 time zones. Why do you think this is?
It takes the Earth 24 hours to rotate on its axis!
This explains why there are 24 time zones.
Each time zone is 15° wide, roughly two lines of longitude.

20. Time Zones

22. International Date Line
Each time you travel through a time zone, you gain or lose time until you gain or lose an entire day.
International Date Line: 180° meridian, serves as the transition line for calendar days.
Imaginary line runs through the Pacific Ocean.
Traveling west: lose a day
Traveling east: gain a day

23. Let’s See it in Practice
Today is Monday, September 25.
If you are travelling across the international date line headed east, it would still be Sunday, September 24.
If you were travelling across the international date line headed west, it will be Monday, September 25 or Tuesday, September 26, depending on the time of day you crossed it!